[Clinical Results after Implantation of Epiretinal Visual Prostheses]

Epiretinal visual prostheses have already been implanted in blind retinitis pigmentosa (RP) patients. Here we report on clinical experience with the Argus® II device and the EPIRET 3 device, on the basis of data from patients operated in Germany. Twenty-eight patients were implanted with the Argus II device and followed for up to three years. EPIRET 3 was implanted in six patients for a period of four weeks. With Argus II, an improvement in visual performance was achieved in the majority of cases, as demonstrated by improved localisation of a light spot and a better perception of moving targets. Mobility and self-confidence improved. The main complications were conjunctival erosion due to the combined extra- and intraocular concept of the device. Among the 28 implanted systems, two needed to be removed because complications refractive to treatment. In contrast, EPIRET 3 is a fully intraocular epiretinal system. During a four week implantation, period thresholds were recorded and exhibited high variability between subjects. However, patients were able to recognise simple patterns. Epiretinal implants for electrical stimulation of the retina should be considered to treat advanced photoreceptor degeneration, and thus to restore basic visual functions at an acceptable rate of complications.